It is difficult for polymers to be treated after use due to their resistance to the environment. When polymers are disposed of in a natural environment, they remain for a long time without degradation. It is frequently asserted by environmental pressure groups that the polyolefins can not biodegrade since the molecular weight must be less than 500 for this to occur. Due to low cost and good mechanical properties as compare to other commodity plastics polyethylene’s are world’s most extensively used commodity plastic of the 21st century. Among the applications in all plastics, polyethylene consumption is 64% in packaging and bottles area. In the packaging area, carry bags are regularly used product and are most visible. For easy disposal of polymers naturally in an environment, photodegradable and biodegradable plastics in packaging materials are the best combination to decrease the accumulation of packaging waste in the environment.
Many authors reported that degradation rate of polyethylene is slow. Biodegradable and photodegradable films may be the solution of visual pollution; these polymers broke into small pieces and reduce into low molecular weight. Natural photodegradation of polyolefin is a very slow process; however, many research papers have reported use of transition metals, which act as pro-oxidant. Addition of these pro-oxidants can promote the oxidation of polyolefin in the presence of oxygen and exposure to light/heat. Many pro-oxidant used with plastics include oxide or stearates of metals such as manganese iron, zinc, zirconium, cerium, titanium and cobalt .
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